Just as Kirk had made up his mind that he could sit and watch this brilliant panorama forever, the jungle suddenly fell away, and the car sped up through low, grass-clad hills into a scattered city flung against the side of a wide valley.  There was no sign here of Latin America; this was Yankeeland through and through.  The houses, hundreds upon hundreds of them, were of the typical Canal Zone architecture, double-galleried and screened from foundation to eaves, and they rambled over the undulating pasture land in a magnificent disregard of distance.  Smooth macadam roads wound back and forth, over which government wagons rolled, drawn by sleek army mules; flower gardens blazed forth in gorgeous colors; women and children, all clean and white and American, were sitting upon the porches or playing in the yards.  Everywhere was a military neatness; the town was like the officers’ quarters of a fort, the whole place spick and span and neatly groomed.

Colon had been surprisingly clean, but it was an unnatural cleanliness, as if the municipality had been scrubbed against its will.  Gatun was to the manner born.

“Yonder are the locks.”  Cortlandt pointed to the west, and Kirk saw below him an impressive array of pyramidal steel towers, from the pinnacles of which stretched a spider’s web of cables.  Beneath this, he had a glimpse of some great activity, but his view was quickly cut off as the motor-car rumbled into a modern railway station.

“I’d like to have a. look at what’s going on over yonder,” he said.

“You will have time,” Cortlandt answered.  “Edith will show you about while I run in on Colonel Bland.”

Out through the station-shed Kirk’s hostess led him, then across a level sward, pausing at length upon the brink of a mighty chasm.  It took him a moment to grasp the sheer magnitude of the thing; then he broke into his first real expression of wonder: 

“Why, I had no idea—­Really, this is tremendous.”

At his feet the earth opened in a giant, man-made canon, running from the valley above, through the low ridge and out below.  Within it an army was at work.  Along the margins of the excavation ran steel tracks, upon which were mounted the movable towers he had seen from a distance.  These tapering structures bore aloft long, tautly drawn wire cables, spanning the gorge and supporting great buckets which soared at regular intervals back and forth, bearing concrete for the work below.  Up and out of the depths tremendous walls were growing like the massive ramparts of a mediaeval city; tremendous steel forms, braced and trussed and reinforced to withstand the weight of the countless tons, stood in regular patterns.  In the floor of the chasm were mysterious pits, black tunnel mouths, in and out of which men crept like ants.  Far across on the opposite lip of the hill, little electric trains sped to and fro, apparently without the aid of human hands.  Everywhere was a steady, feverish activity.